<template>
  <div>
    <div class="shopcart">
      <div class="content">
        <div class="content-left">
          <div class="logo-wrapper">
            <div class="logo" :class="{ highlight: totalCount > 0 }">
              <i
                class="icon-shopping_cart"
                :class="{ highlight: totalCount > 0 }"
              ></i>
            </div>
            <div class="num" v-show="totalCount > 0">
              <bubble :num="totalCount"></bubble>
            </div>
          </div>
          <div class="price" :class="{ highlight: totalPrice > 0 }">
            ￥{{ totalPrice }}
          </div>
          <div class="desc">另需配送费￥{{ deliveryPrice }}元</div>
        </div>
        <div class="content-right">
          <div class="pay" :class="payClass">
            {{ payDesc }}
          </div>
        </div>
      </div>
      <div class="ball-container">
        <div v-for="(ball, index) in balls" :key="index">
          <transition
            @before-enter="beforeDrop"
            @enter="dropping"
            @after-enter="afterDrop"
          >
            <div class="ball" v-show="ball.show">
              <div class="inner inner-hook"></div>
            </div>
          </transition>
        </div>
      </div>
    </div>
  </div>
</template>

<script>
import Bubble from "components/bubble/bubble";

const BALL_LEN = 10;
const innerClsHook = 'inner-hook'

function createBalls() {
  let balls = [];
  for (let i = 0; i < BALL_LEN; i++) {
    balls.push({ show: false });
  }
  return balls;
}

export default {
  name: "shop-cart",
  props: {
    selectFoods: {
      type: Array,
      default() {
        return [];
      },
    },
    deliveryPrice: {
      type: Number,
      default: 0,
    },
    minPrice: {
      type: Number,
      default: 0,
    },
    sticky: {
      type: Boolean,
      default: false
    },
    fold: {
      type: Boolean,
      default: true
    }
  },
  data() {
    return {
      balls: createBalls(),
      listFold: this.fold,
    };
  },
  created() {
    this.dropBalls = [];
  },
  computed: {
    totalPrice() {
      let total = 0;
      this.selectFoods.forEach((food) => {
        total += food.price * food.count;
      });
      return total;
    },
    totalCount() {
      let count = 0;
      this.selectFoods.forEach((food) => {
        count += food.count;
      });
      return count;
    },
    payDesc() {
      if (this.totalPrice === 0) {
        return `￥${this.minPrice}元起送`;
      } else if (this.totalPrice < this.minPrice) {
        let diff = this.minPrice - this.totalPrice;
        return `还差￥${diff}元起送`;
      } else {
        return "去结算";
      }
    },
    payClass() {
      if (!this.totalCount || this.totalPrice < this.minPrice) {
        return "not-enough";
      } else {
        return "enough";
      }
    },
  },
  methods: {
      toggleList() {
        if (this.listFold) {
          if (!this.totalCount) {
            return
          }
          this.listFold = false
          this._showShopCartList()
          this._showShopCartSticky()
        } else {
          this.listFold = true
          this._hideShopCartList()
        }
      },
      pay(e) {
        if (this.totalPrice < this.minPrice) {
          return
        }
        this.$createDialog({
          title: '支付',
          content: `您需要支付${this.totalPrice}元`
        }).show()
        e.stopPropagation()
      },
    drop(el) {
      for (let i = 0; i < this.balls.length; i++) {
        const ball = this.balls[i];
        if (!ball.show) {
          ball.show = true;
          ball.el = el;
          this.dropBalls.push(ball);
          return;
        }
      }
    },
      beforeDrop(el) {
        const ball = this.dropBalls[this.dropBalls.length - 1]
        const rect = ball.el.getBoundingClientRect()
        const x = rect.left - 32
        const y = -(window.innerHeight - rect.top - 22)
        el.style.display = ''
        el.style.transform = el.style.webkitTransform = `translate3d(0,${y}px,0)`
        const inner = el.getElementsByClassName(innerClsHook)[0]
        inner.style.transform = inner.style.webkitTransform = `translate3d(${x}px,0,0)`
      },
      dropping(el, done) {
        this._reflow = document.body.offsetHeight
        el.style.transform = el.style.webkitTransform = `translate3d(0,0,0)`
        const inner = el.getElementsByClassName(innerClsHook)[0]
        inner.style.transform = inner.style.webkitTransform = `translate3d(0,0,0)`
        el.addEventListener('transitionend', done)
      },
      afterDrop(el) {
        const ball = this.dropBalls.shift()
        if (ball) {
          ball.show = false
          el.style.display = 'none'
        }
      },
      _showShopCartList() {
        this.shopCartListComp = this.shopCartListComp || this.$createShopCartList({
          $props: {
            selectFoods: 'selectFoods'
          },
          $events: {
            leave: () => {
              this._hideShopCartSticky()
            },
            hide: () => {
              this.listFold = true
            },
            add: (el) => {
              this.shopCartStickyComp.drop(el)
            }
          }
        })
        this.shopCartListComp.show()
      },
      _showShopCartSticky() {
        this.shopCartStickyComp = this.shopCartStickyComp || this.$createShopCartSticky({
          $props: {
            selectFoods: 'selectFoods',
            deliveryPrice: 'deliveryPrice',
            minPrice: 'minPrice',
            fold: 'listFold',
            list: this.shopCartListComp
          }
        })
        this.shopCartStickyComp.show()
      },
      _hideShopCartList() {
        const list = this.sticky ? this.$parent.list : this.shopCartListComp
        list.hide && list.hide()
      },
      _hideShopCartSticky() {
        this.shopCartStickyComp.hide()
      }
  },
  watch: {
    fold(newVal) {
      this.listFold = newVal
    },
    totalCount(count) {
      if (!this.fold && count === 0) {
        this._hideShopCartList()
      }
    }
  },
  components: {
    Bubble,
  },
};
</script>

<style lang="stylus" scoped>
@import '~common/stylus/mixin';
@import '~common/stylus/variable';

.shopcart {
  height: 100%;

  .content {
    display: flex;
    background: $color-background;
    font-size: 0;
    color: $color-light-grey;

    .content-left {
      flex: 1;

      .logo-wrapper {
        display: inline-block;
        vertical-align: top;
        position: relative;
        top: -10px;
        margin: 0 12px;
        padding: 6px;
        width: 56px;
        height: 56px;
        box-sizing: border-box;
        border-radius: 50%;
        background: $color-background;

        .logo {
          width: 100%;
          height: 100%;
          border-radius: 50%;
          text-align: center;
          background: $color-dark-grey;

          &.highlight {
            background: $color-blue;
          }

          .icon-shopping_cart {
            line-height: 44px;
            font-size: $fontsize-large-xxx;
            color: $color-light-grey;

            &.highlight {
              color: $color-white;
            }
          }
        }

        .num {
          position: absolute;
          top: 0;
          right: 0;
        }
      }

      .price {
        display: inline-block;
        vertical-align: top;
        margin-top: 12px;
        line-height: 24px;
        padding-right: 12px;
        box-sizing: border-box;
        border-right: 1px solid rgba(255, 255, 255, 0.1);
        font-weight: 700;
        font-size: $fontsize-large;

        &.highlight {
          color: $color-white;
        }
      }

      .desc {
        display: inline-block;
        vertical-align: top;
        margin: 12px 0 0 12px;
        line-height: 24px;
        font-size: $fontsize-small-s;
      }
    }

    .content-right {
      flex: 0 0 105px;
      width: 105px;

      .pay {
        height: 48px;
        line-height: 48px;
        text-align: center;
        font-weight: 700;
        font-size: $fontsize-small;

        &.not-enough {
          background: $color-dark-grey;
        }

        &.enough {
          background: $color-green;
          color: $color-white;
        }
      }
    }
  }

  .ball-container {
    .ball {
      position: fixed;
      left: 32px;
      bottom: 22px;
      z-index: 200;
      transition: all 0.4s cubic-bezier(0.49, -0.29, 0.75, 0.41);

      .inner {
        width: 16px;
        height: 16px;
        border-radius: 50%;
        background: $color-blue;
        transition: all 0.4s linear;
      }
    }
  }
}
</style>
